The Indian Ocean received a lot of attention before the 1980s, due to its very dynamic seasonal variability in response to reversing monsoon winds. At the turn of the millennium, the discovery of the Indian Ocean Dipole and new work on the Madden-Julian Oscillation underscored the basin’s importance for global climate. This has invigorated efforts to improve observing systems in that basin, which has, in turn, stimulated a renewed interest in characterising and understanding biogeochemical and ecological variability. As a result, significant advances have been made in our understanding of the Indian Ocean’s circulation, interactions with adjacent ocean basins, biogeochemistry and ecology, and its role in regional and global climate. Nonetheless, significant gaps remain in the observing system and our understanding. With one third of the world population living in countries around the Indian Ocean, it is also very important to better understand its response to anthropogenic climate change.

This session invites contributions that address Indian Ocean variability and change across a range of timescales, based on observations, modelling, and theory. In particular, research that focuses on interactions between physical, biogeochemical, and ecological processes in the Indian Ocean and interactions/exchanges between the Indian Ocean and other oceanic basins is encouraged, as well as studies of the Indian Ocean natural decadal climate variability, response to climate change and interaction with the atmosphere at all scales. Contributions are also sought that address research on the grand challenges in the Indian Ocean system, as formulated by the Oceans and climate: variability, predictability, and change (CLIVAR), the Sustained Indian Ocean Biogeochemistry and Ecosystem Research (SIBER), and the International Indian Ocean Expedition 2 (IIOE-2) programs.